Mechanical seals are widely used to provide a seal between a stationary housing, often containing a fluid such as oil, and a rotating shaft that passes through the housing. Typically, such seals include a stationary seal ring (e.g., a stator) about the shaft but fixed to the housing, and another seal ring (e.g., a mating ring or a rotor), which rotates with the rotating shaft.
Contact between the stator and rotor during operation may create heat as a result of frictional effects between the components. If the amount of heat is undesirable, it could potentially reduce the life of or damage the seal, which could cause undesired deformation with respect to the sealing faces of the rotor and/or stator, and could potentially impair other nearby components.
Hydrodynamic seals attempt to reduce friction by including grooves of some form in the sealing face of the rotor, for example, and without limitation, the grooves as described in U.S. Pat. No. 8,474,826 (Villeneuve et al.), which is assigned to the assignee of this application, and is hereby incorporated herein by reference in its entirety. The grooves may facilitate formation of a layer of fluid between a stator and a rotor during operation, which may be referred to as a hydrodynamic film. Under certain conditions, the hydrodynamic film may cause a separation between the stator and rotor, which may be referred to as lift off.